In your experience, is it worth tube rolling with the Moreplay -- is it sensitive to different tubes? Lots of 6V6 out there and they're relatively inexpensive as far as NOS goes these days ....
It really depends on your entire system, not just the Moreplay. The amps, speakers, sources and cabling must also be sufficiently transparent to allow you to hear potential differences.
Given a sufficiently transparent system, the Moreplay will absolutely allow you to hear differences between tubes. Whether the sound is felt to be better or just different depends on the listener’s tastes and preferences. It’s a relatively inexpensive experiment.